1. Field of the Invention
The present invention relates to a soybean processing system for manufacturing deodorized fine soybean powder for use as soybean milk or as a bulking or improver additive to be added to foods such as bread, cakes, and the like, for manufacturing nondeodorized fine soybean powder for use as a soybean curd or "tofu" material, and for manufacturing soybean curd from the nondeodorized fine soybean powder.
2. Description of the Prior Art
Soybeans are a highly nutritious food source having a high protein content, and used as materials for foods such as soybean curd known as "tofu". There has recently been proposed a process of manufacturing soybean curd from nondeodorized soybean powder which is produced by dehulling soybeans and processing them into fine powder. Deodorized soybean powder is used as a bulking or improver additive to be added to foods such as bread, cakes, cookies and the like. Japanese Laid-Open Patent Publication No. 48(1973)-19946, for example, discloses a process of manufacturing deodorized soybean powder for food uses. According to the disclosed process, cleaned whole soybeans are first compressed, but not defatted, and then dried in a low-temperature, hot-air atmosphere to the extent that the water content thereof is about 3%. Thereafter, the dried soybeans are cracked into a coarse size of about 10 mesh and dehulled into cotyledons which are then steamed in a steaming pot for a short period of time. Odor is removed from the fat and water is removed from the cotyledons under vacuum suction for a short interval of time. Then, the cotyledones are ground successively into medium and fine sizes in a constant-temperature bath.
The nondeodorized soybean powder and the deodorized soybean powder find respective uses. There has been a demand for a system for efficiently manufacturing these different types of soybean powder.
One process of manufacturing soybean curd from soybean powder is disclosed in Japanese Laid-Open Patent Publication No. 51(1976)-95175, for example. The disclosed process comprises the steps of producing soybean milk by stirring soybean powder and water in a stirring tank to form soybean milk, heating the soybean milk in a heating tank, putting the heated soybean milk in a tiltable tank, and tilting the tiltable tank to discharge the heated soybean milk into a receiver tank containing a coagulant for thereby coagulating the soybean milk therein into soybean curd.
However, the aforesaid steps of the above disclosed are all carried out manually, and hence tedious and time-consuming. It is difficult to effect the steps accurately within respective required time periods, and also to keep resulting soybean curd products uniform in quality at all times.